Signal type torque indicating wrench



M. HATTAN Y SIGNAL TYPE TORQUE INDICATING WRENCH May 4, 1948.

Filed Sept. 13

INVENTOR. MAQ/V #A7-74M Patented May 4, 1948Signaturen;TQRQUEf-'INDICATING Wannen MarklHattan, Dayton, Ohio.App1ieati0n-september-1a l,1944, serial No.y 553,853lv ltr-claims.v(Gis1- 525) (Grantedunder th'ef'aet of MarchV 3,l 188,32 as,

The invention describedghereinrmay bekmanuf faetured and1use-d-byorfor-the Government., fors governmental' purposes', Without theraymeutsteme of any royalty thereon.

This invention relates to l vvrenhes and more particularly to 1wrenches; for indiatlngf p redeterminable torque stresses,v

In my eependina, application Serial;N-; 544,128'

there is disclosed a turque.. iadieatinefwreuehcomprising a. idexure.-velement adapted te.` treme.-v

mit torque stress fremthebedy'ef. tiiewreueh-te a werk head and toexyindegree. urepertiuuai;

to the degree of transmitted Stresa.. In eeniuueton with the eiure-felementi uae; ie; made of` apair of edntaeteiemente. adaptedferielativemation and. mutual-engagera@ fini reeperiee, to motion of the; Wrenchkbody in transnutting torque Stresa throuehtlieefieieurememberf Mauualadjusting meauaareeprevided calibrated iutorque units wherebyeftheContact` elements are given an initial relativespacing correspendingVIE toa desiredtorduestresa; miette thetianemiaeiou er turque:thruuehthe-iiexure fmemeeabis manuel. feree exertedeu-.fthewprerieirbedr- Mutuelaeu.- gagementof said contactelernents-zoeursresponf. sive to a degreeefgexure predetermiaedbr. theinitial-Seating., the struetule beine-auth thetthe degree of iiexure,vprior to-4` engagement. of the Contact elements is proportional totheinitial.

spacing provided therebetvveenLl Signal. means are incorporated-imthejwrench responsive to .the mutual eueaeemeutei'said.eentaetelements,fea the purpose. of, apprising the.-operator that. the

desired torquerlstress ,hajsbeen reached. It is the object of l myprevsent invention;to provide ,any imF proved structurefor;acvcornplishingthefunctions hereinaboveset-forthbysimp1iflcationofethe .adiuetiusmeans and; other; parte: etthe device ae- Wiiln, be uadereteefi; from; the. deStript-iereA whichfellows. with referente -te-.tiie appended drawiriee in which:

Fie.. 1 Sheva; a. ieueitudiiialf erede: seetieuthreuehthebedyeeawreiieiii;

Fig.Svisianleaterio view-of the Wrenchl' Wrench is disclosed comprisinga handle portion/I audv au eieueated tubular. Sheet 2tv iutearailyformed therewith. Piuetedfat' lwithiuyehe-ik 2' is a flexure. element G-hayinga free end-'G proe truding into a stress;applying;member;seeured` within the shank Zyby alforcefltor the equivaflent. The exure element 6is1`3fdapted5to havea work head` 9flXedlysecured;theretoin. any. suit,-I

` rod I2. rupon movement. of the body member 2y of acam I8., The cam IBis supportedlrotatably amenueueaprir 30,1928'; 37020;@ 757) adapter.I0.. A Contact,l element comprising a rod I is t disposed vWithin the.ileXure element- 6,', and', secured .therein adjacent thepivot fIvbymeans of.

a plug, I3 ,of vinsulating materialz it :being understood. thatfthe,outer end of Contact rod I 2' is firmly, fixedinltheplug I3,.so that thecontact rodV l2 is axially supported withinthe flexureelement 6. and,spaced, from f thel interior surface thereof. Contaet.` rod I2 has afreeend I Za'disposed adjacent` Contact element I4 which. is. radially`disposed relativeeshank- 2v.. and. guided for reciprocation byl aperforationfain the stress` applyingv member` 8, and havingacontact end;Ida'anda canaffolllwver,Y end Mb; The.contact. end Illak isadaptedtolengage thefree end` I2a..of contact about thepivottlwhena.torque., stress is being applied; as will. hereinafter be described. A

spring, I6..islemploye'd tobiasthe cam follower.Y

end I4blagainstthe .rise and fall-cam surface Il on thefexterior,offbodymeinber2.by means o f side flanges I9 and 20, the flange 20Ibeing adapted toA abut shoulder. 22.of` handle portion I andaeollar.23.belngl 'providedsecured by a` force fit or. the. equivalent. around..body memberV 2v tov abutfflange I9v whereby. cam I8.. is retained. in

place on body memberlZ, but permittedrotative freedoini It Willbeunderstoodthat: rotation of cam 18,. effects` reciprooation ofy contactelement Iltherebyspacingfcontactl end Malfrom the free end IZaofcontactlrod, I2.'aocording.to the point of, engagement. of. cam end Mbwith the rise and fall cam surfacell. A. ratchet mechanism generallyvindicatedby 25Yisprovided in collar 23 for coaction with recessesprovided in flange I9V for the*purposeA of holding cam, IBXed. in anypo-v sinon tambienl it has been rotated. Cam, le isA exteriorly providedWithwindicia 2'1 for coaction With'an indei marker 28 on the bodyportion I for V'setting the Wrench to give a signal at adesiredtorque-stress, the indicia 21 being calibrated in torque. umts.'Incorporated withinv handle i are a plurality-ofl flashlight cellslBllaand 30h retained therein by an end cap 3Iv acting through a spring.32 tomaintain series Contact between thefcells and bias the; cel1`30aagainst the center terminal off a 'signer lamp 34- having the peripheralterminal; thereof' threadedly secured in a metallic ring 35. Aninsulating collar 38 supports the metallic ring 35 Within the handleportion Iy and metallic ring 35 is connected by a light. flexible-.Wire3?! to the freeY end I2`a of contact rodi l 2..

able. manner; forexample, asby a iwork= head' 55 BartsMlfllhandlef'poltiln; l al?? P105/Ned1@ that the lighting of lamp 34will be visible to the operator, and protective plugs 4I of suitabletranslucent material, either plastic or glass, are secured in ports 40to keep dirt and moisture from having access to the interior of thewrench.

In operation, cam I8 'is rotated until some desred indicia thereon is inalignment with the index marker 28 which serves tov initially spacecontact end I4a of contact element I4 with reference to the free end I2aof contact rod I2 in accordance with whatever portion of cam surface I'Iis in engagement with the cam follower end I4b, as determined by thesetting of the indicia. If torque stress now be applied to the handleportion I, the stress is transmitted through stress applying member 8 tothe iiexure member 6, and thence to the work head 9, causing fieXure offlexure element B to a degree proportional to the stress applied tohandle portion I and simultaneously, due to the pivotal action at 4between handle portion I and lexure ,element 6, contact element I4 movestoward contact element I 2 ultimately Yengaging contact end Iv4aWith'free end I2a. Upon engagement between the contact end Ida. and thefree end I2a,l a series circuit is established starting at the positive-centerterminal of the battery 33a., and going through the centerterminal of the lamp 34, the peripheral terminal thereof, ring 35, wire31, free end I2a of contact rod I2, contact end I4a of contact memberI4, through handle I to cap 3|, spring 32, and the negative casingterminal of cell 3013. Accordingly, lamp 34 will light, the illuminationthereof being visible to the operator through ports 4U as hereinabovedescribed. The structure is so arranged that the higher the torquedesired, the greater will be the initial spacing between the contactelements, whereby a greater` iiexure of the flexure element 6 will berequired to cause engagement between the contact elements, and acorrespondingly greater torque force will be required to be exerted onhandle'portion I before lamp 34 is energized.

Accordingly, it will be seeny that I have provided a simple wrenchstructure wherein torque stresses may be predetermined by an adjustingmeans comprising a minimum of moving elements and I claim as myinvention:

1. In a torque indicating wrench, a body member comprising an elongatedtubular shank, a tubular ilexure member axially disposed in said shankand pivoted thereto adjacent the outer extremity thereof and beingadapted for attachment to a work head exteriorly of said shank, a rotarycam supported for rotation at the inner end of said shank and having arise and fall cam surface, a radially reciprocable cam follower,electrical contact elements adapted for variable relative initialspacing therebetween by reciprocation of said follower, said followerbeing` associated with one ofsaid contact elements, rotation of elementsbeing movable with said body member4 whereby said elements are adaptedfor relative motion to a point of mutual engagement operative toAenergize a signal, the degree of iiexure of said flexure member prior tosaid engagement being proportional to the stress transmittedtherethrough and to 'the initial spacing provided 4 between said contactelements by rotation of said cam. Y

2. In a torque indicating wrench, a body member and a flexure member,pivot means whereby said body member is pivoted t0 said flexure member,said exure member having means thereon adapted for attachment to a workhead, means carried by said body member adapted to engage said ilexuremember to transmit torque stress from said body member to said workhead, contact means in said body member comprising variably spaceablecontact elements, one of said contact elements being movable with saidbody member and another cf said elements being secured to said ilexuremember adjacent said pivot means, motion .of said body member intransmitting stress to said 'flexure member being operative to causeengagement of said contact elements for energizing a signal, and meansproviding adjustable initial spacing between said contact elementscomprising a cam member having a cam surface, one of said contactelements comprising a contact end and a follower end adapted to engagesaid cam surface. y

3. In a torque indicating Wrench, a substantially hollow body member anda iiexure member supported therein, said exure member being adapted totransmit torque stress from said body member to a work head secured onsaid flexure member, a first Contact element movable with said bodymember and supported in an aperture of a wall thereof, a second Contactelement supported in the interior of said body member and securedagainst motion relative to said work head, said Contact elements beingadapted to be initially spaced and to mutually engage to energize asignal in response to motion of said body member in transmitting stressto said fiexure member, and means for initially spacing said contactelements comprising an adjustable cam supported on the exterior of saidbody member and having a rise and fall cam surface directed toward saidsecond contact element and operative to move said rst contact elementrelative to said second contact element in response to adjustment ofsaid cam, whereby the torque stress transmitted through said iiexuremember prior to engagement of said contact elements is proportional tosaid initial spacing.

4. In a structure as set forth in claim'S, wherein said rst contactelement protrudes through the wall of said body member and is providedwith an exteriorly disposed follower end for engagement with said cam,said cam being rotatably supported on the exterior of said body member.

5. In a structure as set forth in claim 3, wherein said first contactelement protrudes through the wall of said body member and is providedwith an exteriorly disposed follower for engagement with said cam, saidcam being rotatably supported on the exterior of said body member andsaid rst contact element comprising an integral substantiallycylindrical member spring biased into engagement with said cam surfaceand adapted for sliding and reciprocal motion through the aperture ofsaid-wall responsive to adjustment of said cam.

6. In a structure as set forth in claim 3 wherein said rst contactelement protrudes through the wall of said body member and has anexterior end adapted for engagement with said cam, a stress applyingmember disposed within said body member and adapted to transmit torquestress from said body memberto said flexure member and having anaperture in substantial registration with said body member aperture,said iirst contact element being supported within the aperture of saidstress applying member and .adapted for reciprocable motion therein, anda spring disposed about said contact element and arranged to abutagainst said stress applying member and the exterior` end of said iirstcontact element to maintain said first contact element in operativeengagement with the rise and fall surface of said cam.

7. A torque indicating wrench comprising a body member, a fiexure membermovably mounted with respect to said body member and having a workheadrigidly mounted on one end thereof, means on said body memberengageable with said flexure member adjacent the other end thereof, saidiiexure member being adapted to transmit torque stress from said bodymember to said work head and to iiex in proportion to the degree oftransmitted stress, a pair of contact elements carried by the bodymember and exure member respectively and adapted for mutual engagementby motion of said body member in exing said flexure member, said mutualengagement being effective to operate a signal, said contact elementsbeing adapted for variable initial spacing therebetween whereby thedegree of exing of said ilexure member prior to engagement of saidcontact elements is proportional to said initial spacing, and means foradjusting said initial spacing comprising a rotary cam radially disposedabout said body member, one of said Contact elements having a contactend adapted to be adjusted toward said other contact element byengagement of. a portion of said one cont-act element with said rotarycam and upon rotation of said cam in one direction.

8. A torque indicating wrench as set forth in claim 7, wherein said camcomprises a rise and fall surface arcuately encompassing said onecontact element, said one contact element comprising a member having afollower end adapted to engage said cam surface and having a, contactend adapted for reciprocable movement relative to said other contactelement upon actuation of said follower end by said cam, for Varying theinitial spacing between said contact elements, and spring means carriedon said one contact element to provide for continuous engagement betweensaid follower end and said rise :and fall cam surface.

9. A torque indicating wrench comprising a hollow body member, a exuremember movably mountedin said body member and engageable by means insaid body member to transmit torque stress from said body member to awork head connected to said flexure member, a pair of contact elementswithin said body member, one being carried by said body member and theother being movably mounted in said body member and actuated by a.portion of said fiexure member, means responsive to mutual engagement ofsaid contact elements to energize a signal, said contact elements beingadapted for variable initial spacing therebetween whereby the degree of.ilexing of said exure member prior to engagement of said contactelements is proportional to said initial spacing, means for adjustingsaid initial spacing comprising a cam having a rise and fall cam surfacearcuately disposed about one of said contact elements and radiallydisposed 4about said body member, said one contact element being adaptedfor reciprocable movement relative to said other contact element andhaving a follower end operative by rotary motion of said cam to effectreciproc-ation of said one contact element, and means providingengagement between said follower end and said rise and fall cam surface.

10. In a torque indicating wrench as set forth in claim 9, wherein saidbody member comprises an elongated tubular shank and a handle portion,said cam comprising a ring-like member having side anges and a rise andfall surface peripherally disposed internally therein, said cam beingadapted to be rotatably supported by said side flanges on said tubularshank, said follower end of said one contact element being disposedbetween said flanges, a perforation in said tubular shank through whichsaid contact element extends tow-ard said other contact element and astress applying member disposed between said body member and saidflexure member and adapted to transmit torque stress therebetween.

MARK HATTAN.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 2,225,420 Mandi Dec. 17, 19402,242,613 Mandl May 20, 1941 2,320,023 Zimmerman May 25, 1943 2,367,224Larson et al. Jan. 16, 1945 2,367,247 Valerino et al. Jan. 16, 1945

